Proton therapy developer Mevion Medical Systems has closed a $45 million investment from venture capital firms.
Mevion received the money from healthcare venture capital firm ProQuest Investments and a group of its existing investors. Mevion makes the Mevion S250 proton therapy system, and proceeds from the investment will be used to accelerate the manufacture and worldwide deployment of the system, the company said.
Mevion S250 has not yet received clearance from the U.S. Food and Drug Administration (FDA) for clinical use.
![A 53-year-old patient (patient number four) with a recurrent pituitary adenoma with extension of a cystic component of disease to the medial temporal lobe apparent on MRI (contoured in blue), and extension of disease to the left sphenoid bone and orbital apex apparent on [68Ga]Ga-DOTA-TATE (contoured in yellow).](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/04/pituitary-tumor.QGsEnyB4bU.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
